Stockholders' Equity of the Company and Partners' Capital of the Operating Partnership - Summary of Changes in Noncontrolling Interest (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Noncontrolling Interest [Line Items]
Beginning Balance		$ 34,397			$ 34,397
Net Income	$ 913		$ 1,195		1,450	$ 2,367
Amortization of Unearned Compensation related to the Issuance of LTIP Units (A)	2,053	(2,035)	1,997	$ (4,385)
Other Comprehensive Income (Loss)	(4,463)	(6,330)	2,748	6,549
Unit Distributions	(29,864)	(29,922)	(28,209)	(27,107)
Conversion of Limited Partner Units to Common Stock / General Partner Units			0	0	0	0
Retirement of Limited Partner Units				(934)
Reallocation - Additional Paid-in-Capital	0	0	0	0
Reallocation - Other Comprehensive Income	0	0
Ending Balance	37,859				37,859
Noncontrolling Interest
Noncontrolling Interest [Line Items]
Beginning Balance		34,397		48,077	34,397	48,077
Net Income					1,450	2,367
Amortization of Unearned Compensation related to the Issuance of LTIP Units (A)	511	270			781	0
Other Comprehensive Income (Loss)	(101)	(140)	17	183	(241)	200
Unit Distributions	(652)	(664)	(643)	(775)	(1,316)	(1,418)
Conversion of Limited Partner Units to Common Stock / General Partner Units			(7,318)	(5,009)	0	(12,327)
Retirement of Limited Partner Units				(934)	0	(934)
Reallocation - Additional Paid-in-Capital	(458)	3,238	1,926	292	2,780	2,218
Reallocation - Other Comprehensive Income	1	7			8	0
Ending Balance	37,859		38,183		37,859	38,183
First Industrial, L.P.
Noncontrolling Interest [Line Items]
Beginning Balance		857			857
Net Income	24		22		50	43
Other Comprehensive Income (Loss)	(4,463)	(6,330)	2,748	6,549
Contributions	5		5	116
Distributions	(21)	(43)	(43)	(21)
Conversion of Limited Partner Units to Common Stock / General Partner Units			0	0	0	0
Retirement of Limited Partner Units				(934)
Ending Balance	848				848
First Industrial, L.P. \| Noncontrolling Interest
Noncontrolling Interest [Line Items]
Beginning Balance		857		779	857	779
Net Income					50	43
Contributions	5		5	116	5	121
Distributions	(21)	$ (43)	(43)	$ (21)	(64)	(64)
Ending Balance	$ 848		$ 879		$ 848	$ 879

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